hey sorry for the late response, no necessarily i used 0,1,2 because is easier to spot, but you can replace the numbers with groups as you did.
the structure i made there is basically toggling 3 numbers, if is 0 is GameON if is 1 is GameOver if is 2 game is paused.
now i used 2 buttons to toggle them, but you need to replace those conditions where i used the buttons to whenever ur player is losing the game or pauses the game. other than that they are all kinda the same structure in most of the Construct games. now u can use as i said above groups, but groups are just a fancy boolean with text over them. a group kinda is the same as a variable that u set it on or off. so u can use what u feel you understand better, just the conditional logic of the code needs to be something similar.
if players dies set variable 1 if player pressed pause button set variable to 2 otherwise variable should be 0 and game playable.